1. Field of the Invention
The present invention relates to a vacuum processing apparatus and substrate transfer method, and more particularly to a vacuum processing apparatus configured to perform vacuum processing such as etching, film forming, or the like on a processing substrate such as a semiconductor wafer, a glass substrate for a liquid crystal display device, or the like.
2. Description of the Related Art
Conventionally, in a fabrication process of a semiconductor device, a vacuum processing apparatus configured to perform vacuum processing such as etching, film forming, or the like on a processing substrate such as a semiconductor wafer, a glass substrate for a liquid crystal display device, or the like under a vacuum atmosphere is widely used.
As an example of such a vacuum processing apparatus, there is a plasma processing apparatus which applies a plasma on a processing substrate to perform processing such as etching, film forming, or the like. The plasma processing apparatus accommodates a processing substrate in a processing chamber and makes a predetermined vacuum atmosphere inside the processing chamber to generate a plasma. For this purpose, the processing chamber is provided with a vacuum pump such as a dry pump, a turbo pump, and the like which vacuum evacuates the inside of the processing chamber.
Further, for purposes of improving a throughput, achieving unmanned operation by automatic transfer, and the like, in many of the above-described plasma processing apparatuses, carrying and transferring of a processing substrate into/from the above described processing chamber are automatically performed by a transfer mechanism. Furthermore, for purposes of performing such automatic transfer and plasma processing efficiently as well as decreasing a so-called footprint so as to effectively utilize spaces, there is also a type of the plasma processing apparatus which has a plurality of processing chambers and cassette chambers provided in the vicinity of a transfer chamber accommodating a transfer mechanism and is configured to transfer processing substrates from the inside of the cassette chambers to the processing chambers by the transfer mechanism provided inside the transfer chamber, and to transfer the processed substrates from the processing chambers to cassettes inside the cassette chambers.
In such a case, a vacuum pump is provided in each of the processing chambers, the transfer chamber, and the cassette chambers in order to keep a predetermined vacuum state inside these chambers (refer to Japanese Patent Application Laid-open No. Hei 11-204508 for example).
As described above, a conventional vacuum processing apparatus such as the plasma processing apparatus or the like is intended for enhancement of processing efficiency, effective utilization of spaces, and the like by appropriately combining the processing chamber, the transfer chamber, the cassette chamber, and the like.
However, in recent years, it has become indispensable to conserve energy in respective industries. For this purpose, the vacuum processing apparatus is required to conserve more energy as compared to conventional ones to thereby decrease power consumption or the like. On the other hand, it is necessary to avoid decrease of productivity caused by, for example, decrease of yield or the like. Therefore, energy conservation without causing the decrease of productivity is desired.